A switch device is used, for example, for opening and closing of an electric circuit. The switch device used for opening and closing of an electric circuit may be referred to as an opening/closing device. For example, a switch device is configured by a movable contact terminal (referred to as a movable contact point) and a fixed contact terminal (referred to as a fixed contact point), and a circuit is formed by the movable contact terminal being moved to contact a contact surface of the movable contact terminal with a contact surface of the fixed contact terminal and a current flows. The state of the current flowing is referred to as a state of close. A state where a current does not flow in the circuit is set by an operation of moving the movable contact terminal to separate the contact surface of the movable terminal from the contact surface of the fixed contact terminal. The state where a current does not flow is referred to as a state of open. The movable contact terminal is constructed to maintain the state of open or close, and the state does not change if some vibration is given.
There are the following devices as an example of a device to which a switch device is applied.
For example, a certain remote-control device (part 1) includes a wireless IC tag. The remote-control device receives a radio frequency from a device main body by turning a switch ON. A power supply voltage is generated in the wireless IC tag by the radio frequency received, which enables transmission of data stored. For example, the switch is turned ON by moving the movable contact terminal so that the contact surface of the movable contact terminal makes contact with the contact surface of the fixed contact terminal.
Moreover, for example, a certain remote-control device (part 2) includes a wireless IC tag. The remote-control device has a contact type switch in a part of an electric circuit constituting an antenna of the wiress IC tag. The remote-control device causes an antenna characteristic to change by ON/OFF of the switch. By the characteristic of the antenna being changed, a detection device having a radio frequency tranceiver function detects presence or absence of a response signal from the wireless IC tag, and outputs a detection signal based on the presence or absence of the response signal. A predetermned device operates based on the detection signal output from the detection device.
There is a non-contact type switch other than the above-mentioned contact type switch having the movable contact part and the fixed contact part.
For example, a certain remote-control device (part 3) has a detection device provided with a radio frequency transceiver function and an operation part having a function to return a response signal based on a radio frequency signal transitted from the detection device. The operation part includes a wireless tag. The operation part is provided in a movable open/close member that opens and closes an opening part of an accomodation device. An detection antenna connected to the detection device to perform transmission and reception of radio frequency between the operation part is provided in the vicinity of the opening part in the accommodation device, and a switch for activating or inactivating the signal transmission function of the radio tag is provided in the operation part. A predetermined device is caused to be operated based on the detection signal which the detection device outputs by detecting a presence of a response signal from the radio tag.
Moreover, a certain non-contact short distance communication device (part 4) has a first communication unit to which a first antenna is connected and a second communication unit to which a second antenna is connected. The first and second communication units perform non-contact sort distance communication according to an electromagnetic coupling formed by the first and second antennas. It has an operation means for supplying an operation instruction signal to the second communication unit, and the second antenna and the second communication unit are incorporated in a case. The case is provided at an arbitrary position with respect to the first antenna so that an electromagnetism coupling is formed by the first and second antennas. For example, the first antenna is arranged in an instrument panel.